Erratum to: Concerning the capability of monitoring the condition of coal bed by tomography based upon the representation of object model using Chebyshev polynomialsLarisa Nazarova, Leonid Nazarov, Maxim Protasov, Anton Panov and Petr KonicekE3S Web Conf., 56 (2018) 01026DOI: https://doi.org/10.1051/e3sconf/20185601026